The Jason Alexander era at Reprise Theatre Company

“Once on This Island,” a tale of love and redemption in the Caribbean, marks a new beginning for L.A.’s leading presenter of old musicals.

“Island,” which opens Wednesday at UCLA’s Freud Playhouse, is the first show of Reprise Theatre Company‘s first full season under artistic director Jason Alexander, who is busily reimagining the 12-year-old organization.

“After more than a decade, we need a radically different vision,” says the actor-director, best known for playing George Costanza on TV’s “Seinfeld.” “A vision defined mostly by the expansion of the kind of work we are willing to do and the people we hope to attract.”

The nonprofit subscription series, formerly known as Reprise! Broadway’s Best in Concert, will continue to specialize in revivals, especially of less frequently seen pieces, but will place greater emphasis on reflecting social and artistic diversity and making more adventurous choices about programming and staging.

Alexander says “Island,” which ran on Broadway in the early ‘90s, is “more modern than what we usually do.” Stephen Flaherty and Lynn Ahrens’ reggae-calypso score will be infused with hip-hop, jazz and the blues. “The show gives African American actors an opportunity, but it’s not just about the black experience; its Romeo-and-Juliet story is universal.”

Besides preserving the past, Alexander wants Reprise to help define the future of the American musical by developing original work and expanding its education programs. (He hopes to establish a conservatory one day.)

Before all that can happen, Alexander says, he needs to fix a few basic problems.

Journalist-turned-producer Marcia Seligson started the company in 1997 as a West Coast version of New York City Center’s highly regarded Encores! Great American Musicals in Concert. Encores’ truncated rehearsal and performance schedules have proved attractive to busy Broadway stars. Limited production costs make it possible to mount works others couldn’t afford to because of narrow box office appeal.

Reprise’s inaugural show -- a staged reading of “Promises, Promises” that starred Alexander -- sold out its initial run as well as a return engagement. Over the years, the readings evolved into full-scale productions, albeit without any substantial easing of time and budget constraints.

“As a result,” says Alexander, “our sets and costumes have been underwhelming. We’ve also been guilty of mixed quality in our work. One production would be extraordinary and one or two after that would not.”

Alexander and producing director Susan Dietz, both of whom arrived last year, are trying to figure out ways to maintain high standards despite the tight turnarounds. “We have to enhance what is now a punishing process,” says Dietz, a New York and L.A. producer who has run theaters of all sizes. “We have two weeks to put on a show, which gives us no room for any kind of emergency or setback. And live theater is full of those.”

There’s not much hope of extending schedules because actors are leery of making long commitments. So Alexander is seeking artists who “actually enjoy the challenge of doing quality work in little time.” He also is trying to raise money by adding board members and recruiting donors. Last season, three quarters of the company’s income came from ticket sales, the rest from contributions. “We’re now at a point where each production costs half a million dollars,” he says.

Reprise playgoers tend to be older and many are stage buffs. “They are a wonderful group,” says Alexander, “but one that is diminishing.” He intends to look beyond the traditional songbook to entice a younger, more diverse audience. Too often, shows may have been selected based on their composers and hit numbers and not on how well they work as evenings of entertainment. Aficionados might tolerate a creaky plot for the chance to see -- or hear -- a classic being brought to life. “But,” says Alexander, “I don’t think most of Los Angeles is particularly interested in museum theater.”

In some cases, he notes, “we can take plays that have lost their juice and reinvigorate them while still being very respectful.” Last season, for instance, Alexander transported the ‘50s hit “Damn Yankees” to the soulful ‘80s. “We gave it a new feel, without ripping the show apart.”

Alexander got involved with Reprise thanks to a cold call from Seligson. She was seeking theater pros who could help her start her musical series. Before he moved here to shoot “Seinfeld,” Alexander had spent more than a decade working in New York. He made his Broadway debut in 1981 in Stephen Sondheim’s “Merrily We Roll Along” and won the 1989 Tony for best actor for “Jerome Robbins’ Broadway.”

Not only did Alexander agree to join Seligson, he suggested the first show: “Promises, Promises,” the ‘60s Burt Bacharach-Hal David-Neil Simon adaptation of Billy Wilder’s movie “The Apartment.”

The company built a following by dusting off such oldies as “The Boys From Syracuse” (with David Hyde Pierce) as well as offering up more familiar pieces including “Sweeney Todd” (with Christine Baranski and Kelsey Grammer).

Alexander, who is 48, did not work with Reprise again until last year, when he was invited to direct “Sunday in the Park With George.” By then, the organization was in transition. Seligson had left in 2005 and was pursuing a new project -- the recent Festival of New American Musicals. Producing director Jim Gardia had assumed her duties in addition to his own.

“We were at a point when, faced with mounting costs and budgetary issues, we had to look to the future,” says Lawrence Y. Iser, president of Reprise’s board of directors. “Also, when the founding artistic director leaves, you need to find a new vision.”

Alexander, as it turned out, had plenty of thoughts about where the company could go. “Jason saw how we could honor our core mission of performing classics and hidden gems,” says Iser, “yet look to the next generation by turning us into a leading producer of musical theater on the West Coast.”

The coming season represents what Alexander calls “an alchemy of my ideas.” Following “Once on This Island” will be the ‘70s wife-swapping comedy “I Love My Wife,” which features music by Cy Coleman and book and lyrics by Michael Stewart. Alexander will star along with Patrick Cassidy, Vicki Lewis and Lea Thompson.

“Man of La Mancha,” the 1966 Tony winner, is “our comfort show,” says Alexander, “an attempt to say to our core that we believe in classic musicals.”

The final production will be the ‘80s cult favorite “Chess,” which has a score by ABBA’s Benny Anderson and Bjorn Ulvaeus and lyrics by Tim Rice. “I won’t be coy,” Alexander says. “If we are able to create a version that could have a life beyond Reprise -- and if we could share in that life somehow -- it could provide an annuity of some sort.”

Indeed, Alexander has hopes of emulating Encores: Several of its revivals have led to commercial runs on Broadway and elsewhere. He would like to start creating new works -- and new artists through programs such as Free Style, in which Reprise matched teenage lyricists with ASCAP composers to produce material for a night of song.

“We have big ideas and big dreams,” Alexander says. “Of course, it may be that we’re just too small for our britches. The underlying fear is always that we won’t be as good as we want to be. Or we’ll be as good as we want to be but we can’t get anybody there to see it.”

No matter what happens, he says, “I’m at a point in life where I relish things that scare me. So I enjoy the fact that pulling off each show is a minor miracle.”

“Once on This Island,” Reprise Theatre Company at the Freud Playhouse, UCLA campus. 8 p.m. Tuesdays through Fridays, 2 and 8 p.m. Saturdays, 2 and 7 p.m. Sundays. Opens Wednesday. Ends Sept. 14. $70 and $75. (213) 365-3500 or www.reprise.org